This innovation relates to a method as well as server and client devices to allow a single subscriber of telecommunications services to swap between devices in real-time within the same instant message session. Existing telecommunications standards GSMA RCS v5.1 and OMA CPM v2.0 currently have multi-device scenarios, but only allow one active device per user in an active chat session. In many cases a SIP CANCEL or other session cancellation message is explicitly sent to the secondary user devices not involved in the session. SIP protocol is described by the IETF RFC document 3265. RCS v5.1 Advanced Communications Services and Client Specifications v 2.0 dated May 3, 2013, details these scenarios in Appendix B. The method described in the RCS specification limits full use of the subscribers client devices. Other known methods for users with multiple devices synchronize the message content and session information using the long term message store after the chat session has ended and allow the user, with a different client to re-open a similar session. The message history for the session is often not available in the new client device at the time the user wants to switch device, or is significantly delayed. What is needed is a method for the subscriber to switch to a different device in real-time, while the chat session is still active.